Trends in productivity 1981-2003 (greening and land degradation)
Description
Unsustainable practices in irrigation and production may lead to increased salinization of soil, nutrient depletion and erosion. An estimated 950 million ha of salt-affected lands occur in arid and semi-arid regions, nearly 33% of the potentially arable land area of the world. Globally, some 20% of irrigated land (450,000 km2) is salt-affected, with 2,500–5,000 km2 of lost production every year as a result of salinity (UNEP, 2008).
